Research on Modular Stator Core Structure of Low-Speed Direct-Drive Permanent Magnet Synchronous Machines

Low-speed direct-drive permanent magnet synchronous machines (LDPMSM) gradually replace traditional drive systems in the industrial field, but large-scale mechanical equipment has problems such as processing and transportation difficulties. Therefore, the modular structure of the stator core can simplify the manufacturing process and improve the utilization rate of silicon steel sheet materials. However, the modular form of the stator leads to a decrease in the strength of the splicing position. In order to study the modular strength of the stator, this paper uses finite element analysis to study the structure selection method. By comparing the strength and stress distribution of the spliced structure under the action of electromagnetic forces, it is found that the strength of the semicircle-core is the best among the three selected structures: semicircle-core, T-core and triangle-core. The stator strength of the semicircular structure at different splice positions is also investigated and it is concluded that yoke splicing is superior to tooth separation. In addition, the influence of shrink range of mechanical shell on stator strength is studied. The influence of positional errors, structural parameters and additional gaps on the strength of the stator due to electromagnetic forces and the action of the machine shell are also considered.